The old saying, “The best thing since sliced bread”, was never a great idea, it was coined in a marketing campaign aimed at selling poor quality bread that would never become stale, but why make an unhealthy product more convenient or less costly. How long does it take to slice bread? Pre-sliced bread is filled with preservatives, dough conditioners and chemicals to keep it from drying out and becoming stale. Natural bread becomes stale quickly, as it should; that is why the French bake three times a day. The benchmark I use is, if a loaf of bread does not get stale I will not buy it again, it means it is filled with artificial ingredients.
Buy authentic, genuine bread and avoid trans-fats as well as preservatives.